The existing 3G and 4G cellular mobile communication systems belong to a typical infrastructure network, and a plurality of small power transmitters are used to replace a high power transmitter. Small coverage corresponding to each small transmission area forms a cell, each cell is allocated with a group of channels corresponding to a group of radio resources, and adjacent cells use different radio resources. Thus, no interference will be formed between the cells. The cells with far distances may repeatedly use the same radio resource (i.e., spatial multiplexing of a radio channel resource), so that the system capacity is greatly enlarged.
D2D (Device-to-Device) communication needs no control of a base station or an access node, thus communication or networking is very flexible. A direct advantage of introducing a terminal self-organization communication manner, namely, a D2D communication manner, between terminals of the cellular mobile communication system lies in that a nearby local service may be directly completed by relay forwarding between the terminals without adopting the base station, thus the occupation on resources of the base station is reduced; on the other hand, the coverage defect of a default network may be compensated to eliminate the defect that some blind areas always exist in the coverage area of the existing cellular mobile communication system; and on the third aspect, power consumption may be reduced, when the communication is implemented by multiple short paths instead of a long path, the sum of the power of the multiple short paths will be smaller than the power necessary for the long path; in addition, the self-organization manner is introduced to improve the flux of the entire mobile communication system and increase the multiplexing space.
By adopting the D2D communication manner, transmission may be performed at a non-authorized frequency band, but the interference of the non-authorized frequency band is uncontrollable, especially more and more services occur on the non-authorized frequency band, the interference will be more and more serious, thus the D2D transmission performance will be affected seriously.